Using Case Studies with Large Classes

Why Use Case Studies?

Case studies are powerful tools for teaching. They explore the story behind scientific research to understand the phenomenon being studied, the question the scientist asked, the thinking they used to investigate it, and the data they collected to help students better understand the process and content of science.

A strength of this approach is that it gives students the chance to consider how they would investigate a topic. Their answers are often similar to what the researchers being studied did. But students also come up with novel perspectives and unique approaches to the problems.

Many BioInteractive resources lend themselves to a case study approach. In most instances, what I ultimately decide is to convert the resource into a case study. For example, the video Animated Life: Mary Leakey is an excellent tool to get students thinking about the logic scientists use to study fossils and extinct species. Data Point resources are also a rich source of figures and questions that can be copied and pasted into a presentation to provide a brief case study that introduces a topic.

The Challenge for Large Classes

Many BioInteractive activities are structured in a way that they are particularly useful for smaller groups and classes. And by smaller, I am thinking of fewer than 50 students. To some colleagues, that may seem to be a large class size. Indeed, in many instances, it probably is more than is optimal.

However, when I refer to large classes, what I am thinking of are the large introductory classes encountered in many colleges and universities in which enrollment can range from 100 to 500 or more depending on the institution. Classes of this size present instructors with the dual challenges of not just numbers but also anonymity. It’s logistically unmanageable to share and distribute printed copies of handouts or worksheets.

How to Scale Up

So how can an instructor promote the interaction that is essential to the success of these types of case study activities in such a large group? These are issues I grappled with when I went from teaching at a small liberal arts college where my classes were smaller than 30 to teaching at a large university with classes of several hundreds. I have found what I think are four parts to an effective solution.

1. Define a learning objective.

First and foremost, whether I have 30 or 300 students, I try to think about why I want to use a particular BioInteractive resource. I consider what it is that I want the students to do or think about while using the resource. How do I want them to be different after completing the assignment? In essence, I define the learning objective so I can determine the most effective platform and approach to deliver the lesson utilized in the resource.

2. Create presentations with strategic pause points.

PowerPoint is a common tool for delivering material in large classrooms. It is quite easy to take images and questions from BioInteractive resource PDFs and insert them into slides. After reading the teaching notes and text in the student handouts, it’s relatively simple to develop the story that weaves the slides together in an interrupted case study. This is a style of case study that progressively leads students through the information with carefully planned “reveals” of information and strategically placed questions as stopping points to ponder the material along the way.

Videos are also fabulous resources to use during interrupted case studies in class. For example, I regularly use the video Niche Partitioning and Species Coexistence, which describes Dr. Rob Pringle’s work on niche partitioning in the savanna, as the core of a video case study in class. After the class watches the video for a few minutes, I stop and ask students about the phenomenon being studied and approaches that could be used to answer different questions.

I often use the following questions/prompts:

• Why would anyone care about factors shaping species presence or absence?
• Think about what factors could be important influences on shaping species richness in a community.

How can we use modern techniques to study what an animal is eating when we can’t watch the animal eat?
The video does an excellent job of addressing these topics and showing how researchers developed a creative approach to applying molecular techniques to answer ecological questions. How awesome is it that one video can help students tie together the central dogma, ecological theory, and community concepts! Depending on how much an instructor wants to structure the video case study in advance, it is even possible to embed small video clips and questions directly into a PowerPoint presentation.

3. Have students use clickers.

How should we tell the scientific story to large numbers of students and engage them in it? Clickers are a particularly helpful tool for asking questions about experiments, concepts, or results, because they present students with a specific moment when they need to choose among different options for a survey of their opinion or decide among right and wrong answers in a multiple-choice question.

For example, I typically start a case study with survey questions asking students to identify what they think is the most important item on a list of potential phenomena or to give their feedback about an issue in a Likert-scale response. Later, as the case study develops, I ask more specific questions about the experiment that require students to predict experimental outcomes or interpret a figure. For example, when I use the video The Effects of Fungicides on Bumble Bee Colonies, I show students several bar graphs with possible outcomes for the experiment and have them pick which they think the researchers will observe. After revealing the actual results, I ask them questions about interpreting the results and whether the results support the experimental hypothesis. I always allow students to talk and help one another during clicker questions to enhance their interaction and give them a choice to go along with a group opinion or answer based on their individual thinking.

4. Flip the classroom.

Another effective way to use BioInteractive resources in large classes is to use videos to flip a class session. BioInteractive animations and short films are rich with information that can pique interest, start discussions, or provide fundamental information. For example, I recently had my students watch the Genes as Medicine short film outside of class time. I asked them to then imagine they were an alien that found this video clip and to consider what information it would give them about life on Earth. This sparked a lively discussion about what life is to start the next class meeting that was more interesting than me going through a checklist of terms and definitions. Students had to uncover the characteristics of life from the video for themselves.

Benefits and Takeaways

What I hope these hints and suggestions from my own experiences show is how relatively simple it can be to scale up these resources to engage a class of any size. When they first encounter case studies, students can be a little unsure about this approach that requires them to talk to one another in a setting where they are expecting to be a face in the crowd. However, after they experience one or two case studies, I can see groups of students talking and exchanging ideas about the case. They are no longer passive listeners sitting in a room but instead have become active problem solvers seeking answers together. I can leave the stage and mingle through the room to listen to their discussions and encourage them as they develop their answers. This also gives me an opportunity to interact with students besides those sitting in the front row and to further develop a sense of community and connection, solving one of the challenges with big classes: anonymity.

It has been my experience that students quickly adapt to and begin to enjoy this approach. Rather than sitting in class watching yet another series of PowerPoint slides flash by, they are thinking and talking about science with one another. After my students talk things through with their neighbors and “shoulder buddies” during a case study, I find that they are more likely to speak up in class during the case study and at other points during the course.

At the beginning of the semester, I can barely get anyone to answer a question. After a few case studies, students begin asking and answering questions (even when we aren’t doing case studies), and the level of participation by different students in the room is noticeably higher. So in addition to case studies being a more interesting way for me as the teacher to present material to students and explore different biological topics, this approach also has the added benefits of helping build confidence within individual students and community among students, which makes a more rewarding and exciting learning environment for everyone.

Educational case studies based on examples of simulated or real research data can engage students in the process of thinking like a scientist, even when it is not possible to get into the field or laboratory to actually run an experiment. They can help overcome the challenges of data analysis and interpretation that are at the core of science education experiences. The collections of different resources available through HHMI BioInteractive provide a menu of modules for instructors to choose from that do just that. They get students to explore important biological topics from a variety of different approaches and look at the world through the lenses of different scientists. Regardless of what the actual format of a resource is when I encounter it, I know that it is possible to scale it up in some way to meet the needs of my classes.

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